MYCOFLORA OF PADDY AND MILLED RICE PRODUCED IN THE REGION OF NORTHEASTERN ARGENTINA AND SOUTHERN PARAGUAY

Thirty samples of paddy rice and twenty-five of milled rice were obtai ned from processing centers located in two northern Provinces of Argen tina and one southern Province of Paraguay. Contaminating fungi were e numerated by direct plating on dichloran rose bengal chloramphenicol a gar and oxytetracycline glucose yeast extract agar before and after su rface disinfection. All fungi were isolated and identified to the genu s lever and percentage infection of samples calculated. Those belongin g to the genera Penicillium, Aspergillus and Fusarium were identified to species level. The surface mycoflora was dominated by storage fungi , notably Penicillium citrinum (73% of samples), P. islandicum (60% of samples), Aspergillus niger, A. flavus and Fusarium semitectum. The m ajor fungi found as internal contaminants of paddy rice were, again, P enicillium citrinum (66% of samples) and P, islandicum (50% of samples ). Milled rice showed a lower level of contamination, but with a simil ar species distribution, Penicillium citrinum and P. islandicum again being the main contaminants. The presence of these species suggests a potential for mycotoxin production. Further studies are needed to esta blish the mycotoxin quality of rice from this region. (C) 1997 Elsevie r Science B.V.